Magnetic head for perpendicular recording

ABSTRACT

Arrangement of the flux enhanced part and the flux enhanced end of a main pole and the front or side surface of the main pole of a single-pole head for perpendicular recording is considered to prevent the influence of the leakage magnetic field from those parts and to enhance a field gradient in a portion for writing the boundary of a bit cell into a recording layer in a profile of a perpendicular magnetic field. A flux enhanced part  26  and a flux enhanced end  39  of a main pole are arranged on a leading side  25  rather than a vertical plane  36  in parallel with the cross track direction including the trailing edge of an air bearing surface of the main pole. Further, the front surface on the trailing side of the main pole is arranged on the leading side rather than the vertical plane. The side surface of the main pole intersecting the cross track direction of the main pole is arranged on the track center side rather than a vertical plane perpendicular to the track width including the end of a track at the edge of the trailing side of the air bearing surface of the main pole. The field gradient of a perpendicular magnetic field on the trailing side of a main pole and both end sides of a track can be steep to realize a higher areal recording density.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a magnetic head forperpendicular recording and a magnetic disk apparatus equipped with themagnetic head for perpendicular recording.

[0003] 2. Description of the Related Art

[0004] To increase a recording capacity per unit area of a magneticdisk, the bit length and the track width must be reduced to decrease thesize of one bit cell as a minimum unit of recording information. In thecurrent longitudinal recording system, however, there arises the problemthat bit cell reduction loses a written signal due to the influence ofthermal fluctuation. To solve this problem, a perpendicular recordingsystem magnetizes a medium in the perpendicular direction to writesignal information.

[0005] The recording head of a magnetic disk apparatus writes signalinformation onto a medium. In the perpendicular recording system, thereare a system which uses a double-layered perpendicular medium having asoft magnetic underlayer and a system which uses a single-layerperpendicular medium not having an underlayer. A structure whichcombines a double-layered perpendicular medium with a single-pole headhaving a main pole and an auxiliary pole can apply a more intensemagnetic field to a medium.

[0006] When the cross-sectional area of a main pole of a single-polehead is flux enhanced to the front end thereof, magnetic flux in themagnetic pole is concentrated on the front end of the main pole so thata locally intense magnetic field can be applied to a medium. When a poletip having a high permeability is arranged on the front end of the mainpole, the flow of magnetic flux at the front end of the main pole can besmooth. Further, the processing dimension accuracy at the front end ofthe main pole can be enhanced.

[0007] The example described in Japanese Published Unexamined PatentApplication No. Hei 11-275188 discloses that when a main pole has a poletip, arrangement of a pole tip and a main pole having the pole tip andarrangement of a pole tip and an auxiliary pole are defined so that themagnetic field gradient of a perpendicular magnetic field component onthe trailing side can be improved. This prevents the influence of amagnetic field from the surface of the main pole having the pole tipopposite to a medium, but does not consider increase of the leakagemagnetic flux by flux enhancing in the main pole and the pole tip.

SUMMARY OF THE INVENTION

[0008] In the above prior art, the leakage magnetic field is locallyincreased due to the influence of abrupt flux enhancing in the fluxenhanced part in the main pole and the pole tip and particularly, theflux enhanced end in which the cross-sectional area of the main pole issmallest in the flux enhanced part, resulting in deterioration of themagnetic field gradient in a profile of a perpendicular magnetic field.In addition, the leakage magnetic field from the front or side surfaceof the main pole or the pole tip will also reduce the magnetic fieldgradient. An object of the present invention is to improve a magneticfield gradient in a distribution of a perpendicular magnetic field whichwrites the boundary of a bit cell, that is, a magnetic field gradient onthe trailing side of a profile of a perpendicular magnetic field in thedown track direction and a magnetic field gradient near both ends of atrack of a profile of a perpendicular magnetic field in the cross trackdirection and to realize a high areal recording density by consideringarrangement of the flux enhanced part or the flux enhanced end of a mainpole or a pole tip and the front or side surface of the main pole or thepole tip.

[0009] In the present invention, part or all of the flux enhanced partor the flux enhanced end of a main pole or a pole tip is arranged on theleading side rather than a vertical plane including the trailing edge ofthe air bearing surface of the main pole so as to improve a magneticfield gradient of a profile of a perpendicular magnetic field on thetrailing side and near both ends of a track width. In addition, thefront or side surface of the main pole or the pole tip is arranged tothe center of the main pole so as to improve a magnetic field gradientof the profile of a perpendicular magnetic field on the trailing sideand near both ends of the track width.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a schematic view of the section of a single-pole headfor perpendicular recording according to an embodiment of the presentinvention;

[0011]FIG. 2 is a schematic view of a magnetic head for perpendicularrecording and a magnetic disk apparatus according to an embodiment ofthe present invention;

[0012]FIG. 3 shows schematic views of the magnetic disk appararusaccording to the embodiment of the present invention;

[0013]FIG. 4 is a schematic view of perpendicular recording;

[0014]FIG. 5 shows schematic views of the magnetic head forperpendicular recording and profiles of a perpendicular magnetic field(a) in the disk rotating direction and (b) in the cross track direction;

[0015]FIG. 6 shows schematic views of the flow of magnetic flux andleakage magnetic flux at the front end of a main pole (a) in the diskrotating direction and (b) in the cross track direction;

[0016]FIG. 7 shows schematic views of the flux enhanced part and theside surface of the main pole according to an embodiment of the presentinvention;

[0017]FIG. 8 shows schematic views of structures near the front end ofthe main pole of (1) a conventional type and (2) this invention of amagnetic head for perpendicular recording for use in a three dimensionalintegral method simulation;

[0018]FIG. 9 is a distribution of magnetic flux density of the magneticpole surface near the front end of the main pole in the conventionaltype head;

[0019]FIG. 10 shows profiles of a perpendicular magnetic field in thedisk rotating direction by the three dimensional integral methodsimulation according to an embodiment of the present invention((B),(C))and the conventional (A) type head;

[0020]FIG. 11 is a schematic view of a magnetic transition width;

[0021]FIG. 12 shows profiles of a perpendicular magnetic field in thecross track direction by the three dimensional integral methodsimulation according to an embodiment of the present invention ((B),(C))and the conventional (A) type head;

[0022]FIG. 13 shows schematic views with respect to arrangement of theflux enhanced part of a main pole and the side surface of the main pole,in the main pole not having a pole tip according to an embodiment of thepresent invention;

[0023]FIG. 14 shows schematic views with respect to arrangement of amain pole, in the main pole having a pole tip according to an embodimentof the present invention;

[0024]FIG. 15 is a schematic view with respect to arrangement of the airbearing surface of a main pole and the main pole, in the main polehaving a pole tip according to an embodiment of present invention;

[0025]FIG. 16 shows schematic views with respect to arrangement of theside surface of a main pole, in the main pole having a pole tipaccording to an embodiment of the present invention;

[0026]FIG. 17 shows schematic views with respect to arrangement of theside surface of a main pole intersecting the cross track direction, inthe main pole having a pole tip according to an embodiment of thepresent invention;

[0027]FIG. 18 shows schematic views with respect to arrangement of theflux enhanced part and the side surface of a main pole in a pole tiphaving a flux enhanced part, in the main pole having a pole tipaccording to an embodiment of the present invention;

[0028]FIG. 19 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform);

[0029]FIG. 20 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform);

[0030]FIG. 21 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform);

[0031]FIG. 22 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform);

[0032]FIG. 23 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform); and

[0033]FIG. 24 shows schematic views of a main pole fabrication processaccording to an embodiment of the present invention (provided that themagnification is not uniform).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1

[0034] Embodiments of the present invention will be describedhereinbelow with the drawings. FIG. 2 shows a schematic view of amagnetic disk apparatus using the present invention (provided that themagnification of the drawing is not uniform). The magnetic disk unitreads and writes a magnetization signal on a magnetic disk 11 by amagnetic head 14 attached to a slider 13 fixed onto the front end of asuspension arm 12. The direction of an air in-flow side 31 of the slider13 is called a leading side. The direction of an air out-flow side 30 iscalled a trailing side. The direction to define a geometric track width5 orthogonal to a disk rotating direction 17 is called a cross trackdirection 6. Gimbals, not shown, are formed at the front end of thesuspension arm 12. FIG. 3 shows schematic views of the magnetic diskapparatus.

[0035]FIG. 4 shows a schematic view of perpendicular recording. Thedownstream side in the rotating direction of a perpendicular magneticrecording medium is the trailing side, and the upstream thereof is theleading side. A magnetic circuit is formed such that magnetic flux 33from a main pole 1 passes through a recording layer 19 and an underlayer20 into an auxiliary pole 3. The cross-sectional area of the main pole 1is smaller than that of the auxiliary pole 3. The magnetic flux isconcentrated onto the front end of the main pole. A magnetizationpattern is recorded onto a portion immediately under the main pole ofthe recording layer.

[0036] FIGS. 5(a) and 5(b) respectively show schematic views of aprofile 35 of a perpendicular magnetic field in the magnetic diskrotating direction 17 and a profile 35 of a perpendicular magnetic fieldin the cross track direction 6 by a combination of a double-layeredperpendicular medium having an underlayer and a single-pole head.

[0037] FIGS. 6(a) and 6(b) respectively show schematic views of the flowof magnetic flux in the disk rotating direction 17 and in the crosstrack direction 6 near the front end of the main pole. Near the frontend of the main pole, there are a structure in which the area of thecross section in parallel with an air bearing surface 28 of the mainpole is reduced, that is, a flux enhanced part 26, and a portion inwhich the degree of reducing the area of the cross section is changed,that is, a flux enhanced end 39. The magnetic field profile as shown inFIG. 5 is formed by the sum of magnetic flux flowed from the air bearingsurface 28 of the main pole 1 to the recording layer 19 and magneticflux leaked from the flux enhanced part 26 and the flux enhanced end 39of the main pole and the front surface 40 and the side surface 29 of themain pole, that is, leakage magnetic flux 34.

[0038]FIGS. 1 and 7 show schematic views of a structure near the frontend of the main pole according to an embodiment of the presentinvention. As shown in FIG. 7, the main pole 1 has a portion exposedfrom the air bearing surface of the main pole to define a track width,that is, a pole tip 27, a portion whose cross section is decreased as itapproaches the air bearing surface 28, that is, the flux enhanced part26, and a portion in which the degree of reducing the cross-sectionalarea is changed, that is, the flux enhanced end 39. In the presentinvention, as shown in FIG. 1, the flux enhanced part 26 and the fluxenhanced end 39 are arranged on a leading side 25 with respect to thepole tip 27.

[0039] Using the results calculated from a three dimensional integralmethod, profiles of a perpendicular magnetic field of heads ofconventional type and this embodiment are compared. FIG. 8 showsschematic views of the cross section near the front end of the main polein the head structures used in the calculation. FIG. 8(A) shows astructure near the front end of the main pole in the conventional typehead. FIG. 8(B) shows a structure according to this invention in whichthe front surface on the trailing side of the main pole in FIG. 8(A) istilted so that the flux enhanced part 26 and the flux enhanced end 39 ofthe main pole are arranged on the leading side rather than a verticalplane in parallel with the cross track direction including the trailingedge of the air bearing surface of the main pole, and is envisaged inorder to confirm the effect of arrangement in the present invention.FIG. 8(C) shows a structure according to this invention in which theflux enhanced part 26 and the flux enhanced end 39 are moved backwardand arranged on the leading side rather than the pole tip.

[0040]FIG. 9 shows a distribution of magnetic flux density of themagnetic pole surface of the conventional type head of FIG. 8(A). Thethick line indicates values in which a component of magnetic fluxdensity perpendicular to the magnetic pole surface traced from the airbearing surface in the vertical direction in the center of the frontsurface of the main pole is normalized by a component of perpendicularmagnetic flux density near the center of the air bearing surface of themain pole. For comparison, the thin line indicates normalized componentsof magnetic flux density calculated by a finite element method in a twodimensional head in which an in-plane structure in the disk rotatingdirection is assumed and the flux enhanced part and the flux enhancedend are not considered. In the head without the flux enhanced part andthe flux enhanced end , the magnetic flux density is abruptly decreasedas leaving from the air bearing surface of the main pole. In the threedimensional head structure, the magnetic flux density leaked by fluxenhancing is not monotonously decreased, but is maximum near the fluxenhanced end. The flux enhancing increases the magnetic field intensity.On the other hand, the leakage magnetic flux from near the flux enhancedend results in deterioration of the magnetic field gradient not seen inthe head without the flux enhanced part and the flux enhanced end. Hereis shown the distribution of magnetic flux density of the magnetic polesurface on the trailing side and the leading side of the flux enhancedpart and the flux enhanced end. This is the same for the magnetic polesurface intersecting the cross track direction.

[0041]FIG. 10 shows the profiles 35 of the normalized perpendicularmagnetic field in the disk rotating direction 17 in the center of thethickness direction of the recording layer and a track center 7 in therespective structures of FIG. 8. A magnetic spacing from the air bearingsurface of the main pole to the surface of the recording layer 19 is 15nm. A film thickness of a portion exposed to the air bearing surface ofthe main pole or the pole tip is 400 nm. A geometric track width is 150nm. A saturation magnetic flux density of the main pole and the pole tipis 1.8T(tesla). As compared with the conventional type (A), the magneticfield intensity is lowered at the skirt of the profile on the trailingside in the structures (B) and (C) according to this invention. This isbecause the structures according to this invention decrease theinfluence of the leakage magnetic flux from the flux enhanced part andthe flux enhanced end of the main pole and the front surface of the mainpole. TABLE 1 Normalized Maximum Field gradient field gradientTransition Linear magnetic field [Oe/nm] ×10³ [1/nm] width density [kOe]@5.0[kOe] @5.0[kOe] [nm] [kFCI] (A) 12.3 53.3 4.33 46.5 546 (B) 11.960.1 5.05 38.6 656 (C) 11.4 58.8 5.16 45.6 558

[0042] Table 1 shows field gradients on the trailing side normalized bythe maximum magnetic field of the profiles 35 of the perpendicularmagnetic field of the three structures of FIG. 8. In consideration ofthe case of writing onto a medium having a coercive field of 5 kOe, thefield gradients of the perpendicular magnetic field component on thetrailing side at a field intensity of 5 kOe are compared. In thestructures according to this invention of FIG. 8, as compared with theconventional type (A), the normalized field gradients are improved inthe order of (B) and (C). Further, effects given to read-writecharacteristic by the profile 35 of the perpendicular magnetic field arecompared using transition width. Table 1 shows transition widthspredicted when assuming the respective magnetic field profiles. A mediumhaving a coercive field of 5 kOe, a saturation magnetization of 250emu/cm³, and a recording layer film thickness of 20 nm is assumed here.An overview of a read/write characteristic prediction tool correspondingto a perpendicular recording system used for calculating the transitionwidth has been presented in The 23rd Japan Applied Magnetics Society'sScientific Lecture 5aB-6 (1999). The transition width is a variableshowing the transition region of isolated transition, as shown in FIG.11. A magnetization pattern showing signal information at apredetermined recording density is assumed to be represented by linearsuperposition of the isolated transition. To realize read/write withinthe range of a predetermined error rate, it can be considered that thetransition width must be below the bit length. As shown in Table 1, ascompared with the conventional type (A), in this invention (B), thetransition width is reduced and the linear density capable of read/writein which the transition width is assumed to be equal to the bit lengthis enhanced by about 100 kFCI (Flux Change per Inch) when expressed bythe transition number per 1 inch. In the structure (C) according to thisinvention, since the maximum magnetic field is about 1 kOe smaller thanthat of the conventional type (A), the field gradient beforenormalization is lower than that of (B) and the linear density capableof read/write to be assumed is lower than that of (B). Still (C) is themost effective structure with respect to the normalized field gradient.Under the conditions that an equal maximum magnetic field is provided byfine adjusting an electric current of a coil or the structure near themain pole, the linear density capable of read/write to be assumed can beexpected higher than that of (B). With MKSA unit, 1 Oe=79.6 A/m, 1emu=1.257×10⁻⁷ Wb, and 1 inch=2.54×10⁻² m.

[0043] In the invention of FIG. 8, the flux enhanced part 26 and theflux enhanced end 39 are arranged on the leading side as compared withthe conventional type so that the profile of the perpendicular magneticfield in the cross track direction 6 near the trailing edge of the airbearing surface of the main pole can be also improved. FIG. 12 shows theprofiles 35 of the perpendicular magnetic field from the track center inthe single-side cross track direction in the center in the thicknessdirection of the recording layer immediately under the trailing edge ofthe air bearing surface of the main pole. As compared with theconventional type (A), in (B), the magnetic field of the bottom portionof the magnetic field profile is found to be small. The influence of theleakage magnetic flux from the flux enhanced part 26 and the fluxenhanced end 39 can be reduced at the edge of the track, thus the fieldgradient can be enhanced and the magnetization transition region can besmall. In the structure (C), the arrangement of the flux enhanced part26 and the flux enhanced end 39 is limited as compared with thestructure of FIG. 8(B). As shown in FIG. 8(C), the flux enhanced part 26and the flux enhanced end 39 are arranged on the leading side ratherthan a vertical plane in parallel with the cross track directionincluding the leading edge of the air bearing surface of the main pole.It is thus possible to improve the field gradient in the profile 35 of aperpendicular magnetic field in the cross track direction immediatelyunder the trailing edge and over the entire air bearing surface of themain pole.

Embodiment 2

[0044] FIGS. 13 to 17 list the embodiments of the present invention. InFIG. 13, there are shown structures of the main pole not having the poletip. In FIG. 13(1), the front surface of the main pole on the trailingside intersecting the air bearing surface of the main pole is tilted sothat the flux enhanced part 26 and the flux enhanced end 39 are arrangedon the leading side rather than a vertical plane 36 in parallel with thecross track direction including the trailing edge of the air bearingsurface of the main pole. In FIG. 13(2), the front surface of the mainpole on the trailing side is arranged on the leading side by leaving aportion to define a track width and the trailing edge, and at the sametime, the flux enhanced part 26 and the flux enhanced end 39 arearranged on the leading side rather than the vertical plane 36 inparallel with the cross track direction including the trailing edge ofthe air bearing surface of the main pole. Here, the front surface of themain pole is moved backward to the leading side stepwise, but may begently moved backward. In FIGS. 13(1) and 13(2), the side surface of themain pole, the flux enhanced part and the flux enhanced end are whollyarranged on the leading side. Part of the side surface of the main pole,for example, part of the flux enhanced part 26 on which magnetic flux islikely to be concentrated near the flux enhanced end 39 may be arrangedon the leading side as shown in FIG. 13(3) to obtain the effect.

[0045] When the arrangement of FIGS. 13(1) to 13(3) is further limited,the flux enhanced part 26 and the flux enhanced end 39 are arranged onthe leading side rather than the vertical plane in parallel with thecross track direction including the edge of the leading side of the airbearing surface of the main pole, the influence of the leakage magneticflux from the flux enhanced part 26 and the flux enhanced end 39 can beprevented over the entire air bearing surface of the main pole. Theprofile 35 of a perpendicular magnetic field in the cross trackdirection can be improved over the entire air bearing surface of themain pole.

[0046] In the arrangement of the flux enhanced part 26 and the fluxenhanced end 39 of FIGS. 13(1) and 13(2), the front surface of the mainpole on the trailing side is also arranged on the leading side ratherthan the vertical plane 36 in parallel with the cross track directionincluding the trailing edge of the air bearing surface of the main pole.In other words, the influence of the leakage magnetic flux from thefront surface of the main pole on the trailing side as well as the fluxenhanced part and the flux enhanced end is prevented. In the same manneras FIGS. 13(1) to (3), as shown in FIGS. 13(4) and 13(5), the sidesurface of the main pole intersecting the cross track direction istilted and moved backward by leaving a portion to define a track widthso as to be arranged on a track center 39 side rather than a verticalplane 38 perpendicular to the cross track direction including the edgeof the track of the trailing edge of the air bearing surface of the mainpole. The arrangement of the side surface of the main pole intersectingthe cross track direction can be combined with the respective structuresof FIGS. 13(1) to 13(3).

[0047] When the number of the flux enhanced parts and the flux enhancedends is not one, the effect can be obtained in any position byconsidering the arrangement described here. Arrangement for a positionnear the air bearing surface or the vicinity of a position having alarge flux enhanced angle is considered to obtain a large effect.

Embodiment 3

[0048] FIGS. 14 to 16 respectively show structures when the main polehas the pole tip 27. When the pole tip is provided, it can be expectedthat the accuracy of the track width in the production process isenhanced, and magnetic domain control and a high Bs material such as 55%Fe-45% Ni having a saturation magnetic flux density of 1.6T or CoNiFehaving a saturation magnetic flux density of 2.2T ,or the like are usedto improve the magnetic field intensity. In addition, the distancebetween the main pole and the soft magnetic underlayer is adjusted orthe contact area of the pole tip with the main pole is adjusted, wherebythe magnetic field intensity can be increased. Also in the case that themain pole has the pole tip 27, in order to prevent the leakage magneticfield, an arrangement in which the flux enhanced part 26 and the fluxenhanced end 39 are as far as possible from the trailing edge of thepole tip is considered. In FIGS. 14(1) and 14 (2), the flux enhancedpart 26 and the flux enhanced end 39 are arranged on the leading siderather than the vertical plane 36 in parallel with the cross trackdirection including the trailing edge of the air bearing surface of thepole tip 27. The arrangement of FIG. 14(2) can be applied to any of thefollowing examples. As shown in FIG. 14(3), the positions of the fluxenhanced part 26 and the flux enhanced end 39 in the main pole areconsidered likewise.

[0049] The arrangement is further defined so that the flux enhanced part26 and the flux enhanced end 39 are arranged on the leading side ratherthan the vertical plane in parallel with the cross track directionincluding the edge of the leading side of the air bearing surface of thepole tip. The influence of the leakage magnetic flux from the fluxenhanced part 26 and the flux enhanced end 39 over the entire airbearing surface of the main pole can be prevented. The profile 35 of aperpendicular magnetic field in the cross track direction can beimproved over the entire air bearing surface of the main pole. Forexample, FIGS. 14(1) and 14(3) satisfy this condition, and as comparedwith FIG. 14(2), the profile 35 of a perpendicular magnetic fieldcomponent in the cross track direction can be improved over the entireair bearing surface of the main pole. As shown in FIG. 15, when the poletip is not hexahedral, the flux enhanced part 26 and the flux enhancedend 39 are arranged on the leading side rather than the vertical planein parallel with the cross track direction including the edge of theleading side of the air bearing surface of the pole tip so as to obtainthe same effect over the entire air bearing surface of the main pole.

[0050] In FIGS. 16(1) and 16(2), the front surface on the trailing sideof the pole tip is tilted in the same manner as FIGS. 13(1) and 13(2),and is arranged on the leading side by leaving a portion to define atrack width and the trailing edge so as to be arranged on the leadingside rather than the vertical plane 36 in parallel with the cross trackdirection including the trailing edge of the air bearing surface of thepole tip. The effect for suppressing the leakage magnetic flux from thefront surface on the trailing side of the pole tip can be obtained whenthe main pole is arranged on the trailing side rather than the pole tip,as shown in FIGS. 16(3) and 16(4). As in FIG. 16(1), the front surfaceon the trailing side of the pole tip is tilted so as to obtain theeffect. FIGS. 16(3) and 16(4) are particularly effective methods whenthe main pole is sufficiently away from the air bearing surface of thepole tip.

[0051] In FIG. 17, in the same manner as FIGS. 13(4) and 13(5), the sidesurface of the pole tip intersecting the cross track direction is tiltedand is moved backward by leaving a portion to define a track width so asto be arranged on the track center 39 side rather than the verticalplane 38 perpendicular to the cross track direction including the edgeof the track of the trailing edge of the air bearing surface of the poletip. The arrangement of the side surface of the main pole intersectingthe cross track direction can be combined with the respective structuresof FIGS. 14 to 15. The effect for suppressing the leakage magnetic fluxfrom the side surface intersecting the cross track direction can beobtained when the flux enhanced part and the flux enhanced end arearranged on the trailing side rather than the pole tip, as shown in FIG.17(3).

Embodiment 4

[0052] Embodiment 4 shows an embodiment in which the flux enhanced partis provided in the pole tip of the main pole. When flux enhancing isprovided in the pole tip, it can be expected as in embodiment 3, thatthe accuracy of the track width in the production process is enhanced,and magnetic domain control and a high Bs material such as 55% Fe-45% Nihaving a saturation magnetic flux density of 1.6T or CoNiFe having asaturation magnetic flux density of 2.2T , or the like are used toimprove the magnetic field intensity. The distance between the main poleand the soft magnetic underlayer is adjusted or the contact area of thepole tip with the main pole is adjusted so that the magnetic fieldintensity can be increased. The flux enhancing in the pole tip can alsoadjust the magnetic field intensity. As in FIGS. 18(1) and 18(2), whenthe pole tip has the flux enhanced part 26 and the flux enhanced end 39,all the ideas of FIG. 13 can be applied to the structure of the poletip. The effect for suppressing the leakage magnetic flux from the frontsurface on the trailing side of the pole tip, the flux enhanced part andthe flux enhanced end can be obtained when the main pole is arranged onthe trailing side rather than the pole tip, as shown in FIG. 18(3).

Embodiment 5

[0053] An embodiment of a method for producing a magnetic head accordingto the present invention will be described with the drawing. FIG. 19shows schematic views of the production process of the present invention(provided that the magnification of the drawing is not uniform). FIG.19(A) shows a cross section view in the down track direction and FIG.19(B) shows a cross section view in the cross track direction. Ainorganic insulating layer 101 is deposited by sputtering on anon-magnetic base 104 made of alumina titanium carbide. A magnetic layer102 is deposited on the inorganic insulating layer by sputtering, and ispatterned into a required shape to obtain a lower shield. A inorganicinsulating layer 101 and a reading element are formed on the magneticlayer 102 as the lower shield. An upper shield and a magnetic layer 102as the auxiliary pole are formed. The upper shield and the auxiliarypole may be separated into two layers by interposing the insulating filmtherebetween. FIG. 19(a) shows that a resist pattern is formed on theinorganic insulating layer. As the inorganic insulating layer,conventionally used Al₂O₃, SiC, AlN, Ta₂O₅, TiC, TiO₂ and SiO₂ can beused. FIG. 19(b) shows that the magnetic layer is plated. In the case ofusing electroplating, 55% Fe-45% Ni having a saturation magnetic fluxdensity of 1.6T or CoNiFe having a saturation magnetic flux density of2.2T , or the like can be used. As the plating base layer, a magneticlayer of the same composition as the plating layer or a inmagneticinsulating layer may be used. FIG. 19(c) shows that the resist patternis removed. FIG. 19(d) shows that a inorganic insulating layer is formedand the top surfaces of the inorganic insulating layer and the magneticlayer are flattened. In flattening, a polishing method such as chemicalmechanical polishing (CMP) and ion-milling may be used. FIG. 19(e) showsthat a resist pattern for forming a pole tip is formed. FIG. 19(f) showsthat a magnetic layer 102′ as the pole tip is formed. FIG. 19(f′) is across section view in the cross track direction. The shape of the crosssection view in the cross track direction of the magnetic layer 102′ asthe pole tip may be of the shape shown in FIG. 17. FIG. 19(g) shows thatthe resist pattern is removed to form a inorganic insulating layer. Inthe process for exposing the air bearing surface, the air bearingsurface may be on the left side in the drawing from a position 103indicated by a chain line. Using this fabrication method, a magnetichead for perpendicular recording of the present invention having thepole tip can be produced.

[0054]FIG. 20 shows schematic views of another fabrication process ofthe present invention (provided that the magnification of the drawing isnot uniform). FIG. 20(A) shows a cross section view in the down trackdirection and FIG. 20(B) shows a cross section view in the cross trackdirection . The fabrication process before forming a coil is the same asFIG. 19. The production process before forming a coil is omitted in thedrawing. FIG. 20(a) shows that a resist pattern is formed on theinorganic insulating layer. FIG. 20(b) shows that the magnetic layer isplated. FIG. 20(c) shows that the resist pattern is removed. FIG. 20(d)shows that a inorganic insulating layer is formed and the top surfacesof the inorganic insulating layer and the magnetic layer are flattened.In flattening, a polishing method such as chemical mechanical polishing(CMP) and ion-milling may be used. FIG. 20(e) shows that a resistpattern for forming a pole tip is formed. FIG. 20(f) shows that amagnetic layer 102′ as the pole tip is formed. FIG. 20(f′) is a crosssection view in the down track direction. The shape of the wafer view ofthe magnetic layer 102′ as the pole tip may be of the shape shown inFIG. 17. FIG. 20(g) shows that a resist pattern is formed. FIG. 20(h)shows that the magnetic layer 102′ is etched with the resist pattern asa mask to form a slope. The slope may be formed with the flux enhancedpart as shown in FIG. 18(1). Thereafter, the resist pattern is removedto form a inorganic insulating layer. In the process for exposing theair bearing surface, the air bearing surface may be on the left side inthe drawing from the position 103 indicated by a chain line. Using thisfabrication method, a magnetic head for perpendicular recording of thepresent invention having the pole tip can be produced.

Embodiment 6

[0055]FIG. 21 shows schematic views of another fabrication process ofthe present invention (provided that the magnification of the drawing isnot uniform). The drawing is a cross section view in the down trackdirection. The fabrication process before forming a coil is the same asFIG. 19. The fabrication process before forming a coil is omitted in thedrawing. FIG. 21(a) shows that a resist pattern is formed on theinorganic insulating layer. FIG. 21(b) shows that the magnetic layer isplated. FIG. 21(c) shows that the resist pattern is removed. FIG. 21(d)shows that the inorganic insulating layer is formed and the top surfacesof the inorganic insulating layer and the magnetic layer are flattened.In flattening, a polishing method such as chemical mechanical polishing(CMP) and ion-milling may be used. FIG. 21(e) shows that a resistpattern for forming a pole tip is formed. FIG. 21(f) shows that amagnetic layer 102′ as the pole tip is formed. The magnetic layer 102′as the pole tip may be formed with the flux enhanced part as shown inFIGS. 18(2) and 18(3). The shape of the cross section view in the crosstrack direction of the magnetic layer 102′ as the pole tip may be of theshape shown in FIG. 17. FIG. 21(g) shows that a resist pattern isformed. FIG. 21(h) shows that a magnetic layer 102″ is formed with theresist pattern as a mask. Thereafter, the resist pattern is removed toform a inorganic insulating layer. In the process for exposing the airbearing surface, the air bearing surface may be on the left side in thedrawing from the position 103 indicated by a chain line. Using thisfabrication method, a magnetic head for perpendicular recording of thepresent invention having the pole tip can be produced.

[0056]FIG. 22 shows schematic views of another fabrication process ofthe present invention (provided that the magnification of the drawing isnot uniform). FIG. 22(A) shows a cross section view in the down trackdirection and FIG. 22(B) shows a diagram of the air bearing surface. Thefabrication process before forming a coil is the same as FIG. 19. Thefabrication process before forming a coil is omitted in the drawing.FIG. 22(a) shows that a magnetic layer is formed, a inorganic insulatinglayer is formed, and a resist pattern of the shape as shown in thedrawing is formed on the inorganic insulating layer. This is theso-called lift-off method. FIG. 22(b) shows that the inorganicinsulating layer is sputtered. FIG. 22(c) shows that after sputtering,the resist pattern and the non-organic layer attached thereto areremoved. FIG. 22(d) shows that a resist pattern is formed. FIG. 22(e)shows that the magnetic layer is plated. The magnetic layer 102′ as thepole tip may be formed with the flux enhanced part as shown in FIG. 17.The shape of the wafer view of the magnetic layer 102′ as the pole tipmay be of the shape shown in FIG. 17. FIG. 22(f) shows that the resistpattern is removed. Thereafter, a inorganic insulating layer is formed.In the process for exposing the air bearing surface, the air bearingsurface may be on the left side in the drawing from the position 103indicated by a chain line. Using this fabrication method, a magnetichead for perpendicular recording of the present invention having thepole tip can be produced.

[0057]FIG. 23 shows schematic views of another fabrication process ofthe present invention (provided that the magnification of the drawing isnot uniform). FIG. 23(A) shows a cross section view in the down trackdirection and FIG. 23(B) shows a diagram of the air bearing surface. Thefabrication process before forming a coil is the same as FIG. 19. Thefabrication process before forming a coil is omitted in the drawing.FIG. 23(a) shows that a inorganic insulating layer is formed, and aresist pattern of the shape as shown in the drawing is formed on theinorganic insulating layer. This is the so-called lift-off method. FIG.23(b) shows that the inorganic insulating layer is sputtered. FIG. 23(c)shows that after sputtering, the resist pattern and the inorganicinsulating layer attached thereto are removed. FIG. 23(d) shows that aresist pattern is formed. FIG. 23(e) shows that the magnetic layer isplated. FIG. 23(f) shows that the resist pattern is removed. Thereafter,a inorganic insulating layer is formed. In the process for exposing theair bearing surface, the air bearing surface may be on the left side inthe drawing from the position 103 indicated by a chain line. Using thisfabrication method, a magnetic head for perpendicular recording of thepresent invention can be produced.

[0058]FIG. 24 shows schematic views of another fabrication process ofthe present invention (provided that the magnification of the drawing isnot uniform). FIG. 24(A) shows a cross section view in the down trackdirection and FIG. 24(B) shows a diagram of the air bearing surface. Thefabrication process before forming a coil is the same as FIG. 19. Thefabrication process before forming a coil is omitted in the drawing.FIG. 24(a) shows that a inorganic insulating layer is formed, and aresist pattern is formed on the inorganic insulating layer. FIG. 24(b)shows that the inorganic insulating layer is etched with the resistpattern as a mask. In the case of using Al₂O₃, BCl₃ or a mixed gas forBCl₃ and Cl₂ may be used as an etching gas. In the case of using AlN,the chlorine gas may be used. In the case of using Ta₂O₅, TiC, TiC₂,SiO₂, and SiO which facilitate etching, fluorine gas, such as CHF₃, CF₄,SF₆, and C₄F₈,can be used. FIG. 24(c) shows that after etching, theresist pattern is removed. FIG. 24(d) shows that a resist pattern isformed. FIG. 24(e) shows that the magnetic layer is plated. FIG. 24(f)shows that the resist pattern is removed. Thereafter, a inorganicinsulating layer is formed. In the process for exposing the air bearingsurface, the air bearing surface may be on the left side in the drawingfrom the position 103 indicated by a chain line. Using this fabricationmethod, a magnetic head for perpendicular recording of the presentinvention can be produced.

[0059] The process for forming a magnetic layer in the above fabricationmethods described using FIGS. 19 to 24 may be a process for using amagnetron sputtering method with a photoresist as a mask.

Embodiment 7

[0060] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a recording head with amain pole and an auxiliary pole and a read head with a reading element;gimbals for supporting the slider; and a suspension onto which thegimbals are fixed. The basic structure of the head assembly of thisembodiment combines the suspension arm 12 shown in FIG. 2 with themagnetic head slider. Although not shown in the drawing, the gimbals arejoined to the front end of the suspension arm 12. The gimbals and thesuspension arm are different parts, but may be integrally formed at thefront end of the suspension arm 12.

Embodiment 8

[0061] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary head, andin the main pole, part or all of a flux enhanced part in which the areaof the cross section in parallel with an air bearing surface isdecreased as it approaches the air bearing surface and a position of theflux enhanced part closest to the air bearing surface, that is, a fluxenhanced end are arranged on the air in-flow side of the main polerather than a vertical plane in parallel with the cross track directionincluding the edge on the air out-flow side of the air bearing surfaceof the main pole.

Embodiment 9

[0062] An invention described in this embodiment is a head assemblywherein in the main pole of the perpendicular recording head accordingto embodiment 8, part or all of the flux enhanced part or the fluxenhanced end is arranged on the air in-flow side rather than a verticalplane in parallel with the cross track direction including the edge onthe air in-flow side of the air bearing surface.

Embodiment 10

[0063] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, andin the main pole, part or all of the front surface on the air out-flowside of the main pole in the air bearing height direction viewed fromthe air bearing surface intersecting an air bearing surface is arrangedon the air in-flow side rather than a vertical plane in parallel withthe cross track direction including the edge on the air out-flow side ofthe air bearing surface.

Embodiment 11

[0064] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, andin the main pole, part or all of the side surface intersecting the crosstrack direction of the main pole is arranged on the center side of themain pole rather than a vertical plane perpendicular to the cross trackdirection including the edge in the cross track direction of an airbearing surface.

Embodiment 12

[0065] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface to define atrack width, that is, a pole tip, and in the main pole, part or all of apart in which the area of the cross section in parallel with the airbearing surface is decreased as it approaches the air bearing surface,that is, a flux enhanced part and a position of the flux enhanced partclosest to the air bearing surface, that is, a flux enhanced end arearranged on the air in-flow side of the pole tip rather than a verticalplane in parallel with the cross track direction including the edge onthe air out-flow side of the air bearing surface of the pole tip.

Embodiment 13

[0066] An invention described in this embodiment is a head assemblywherein in the perpendicular recording head according to embodiment 12,part or all of the flux enhanced part or the flux enhanced end of themain pole is arranged on the air in-flow side rather than a verticalplane including the edge on the air in-flow side of the air bearingsurface of the pole tip.

Embodiment 14

[0067] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface to define atrack width, that is, a pole tip, and in the pole tip, part or all ofthe front surface on the air out-flow side of the pole tip in the airbearing height direction viewed from the air bearing surface of the poletip intersecting the air bearing surface is arranged on the air in-flowside rather than a vertical plane in parallel with the cross trackdirection including the edge on the air out-flow side of the air bearingsurface.

Embodiment 15

[0068] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface to define atrack width, that is, a pole tip, and in the pole tip, part or all ofthe side surface intersecting the cross track direction is arranged onthe center side of the pole tip rather than a vertical planeperpendicular to the cross track direction including the edge in thecross track direction of the air bearing surface of the pole tip.

Embodiment 16

[0069] An invention described in this embodiment is a head assemblyincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; gimbals for supporting the magnetic head slider;and a suspension arm onto which the gimbals are fixed, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface to define atrack width, that is, a pole tip, and in the pole tip, part or all of apart in which the area of the cross section in parallel with the airbearing surface is decreased as it approaches the air bearing surfaceand magnetic flux is enhanced, that is, a flux enhanced part and aposition of the flux enhanced part closest to the air bearing surface,that is, a flux enhanced end are arranged on the air in-flow side ratherthan a vertical plane in parallel with the cross track directionincluding the edge on the air out-flow side of the air bearing surfaceof the pole tip.

Embodiment 17

[0070] An invention described in this embodiment is a head assemblywherein in the main pole of the perpendicular recording head accordingto embodiment 16, wherein part or all of the flux enhanced part or theflux enhanced end is arranged on the air in-flow side rather than avertical plane in parallel with the cross track direction including theedge on the air in-flow side of the air bearing surface.

[0071] In embodiments 7 to 17, it is possible to provide a head assemblyequipped with the magnetic head according to embodiments 1 to 4 whichcan realize a recording magnetic field profile whose gradient is steep.

Embodiment 18

[0072] As shown in FIG. 3, the magnetic disk unit of this embodiment hasa magnetic disk, a magnetic head slider equipped with recording and readheads, a spindle motor for rotatively driving the magnetic disk in onedirection, a suspension and arm for supporting the slider, and a rotaryactuator for driving the arm. The magnetic disk unit is structured torealize recording by a magnetic field profile whose gradient is steepand enhance a liner density in the disk rotating direction and a trackdensity in the disk radius direction, thereby realizing a high arealrecording density.

Embodiment 19

[0073] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, andin the main pole, part or all of a flux enhanced part in which the areaof the cross section in parallel with an air bearing surface isdecreased as it approaches the air bearing surface and a position theflux enhanced part closest to the air bearing surface, that is, a fluxenhanced end are arranged on the leading side rather than a verticalplane in parallel with the cross track direction including the edge onthe trailing side of the air bearing surface of the main pole.

Embodiment 20

[0074] An invention described in this embodiment is a magnetic disk unitaccording to embodiment 19, wherein part or all of the flux enhancedpart or the flux enhanced end of the main pole is arranged on theleading side rather than a vertical plane in parallel with the crosstrack direction including the edge on the leading side of the airbearing surface.

Embodiment 21

[0075] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, andin the main pole, part or all of the front surface on the trailing sideof the main pole in the air bearing height direction viewed from the airbearing surface intersecting an air bearing surface is arranged on theleading side rather than a vertical plane in parallel with the crosstrack direction including the edge on the trailing side of the airbearing surface.

Embodiment 22

[0076] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, andin the main pole, part or all of the side surface intersecting the crosstrack direction is arranged on the center side of the main pole ratherthan a vertical plane perpendicular to the cross track directionincluding the edge in the cross track direction of an air bearingsurface.

Embodiment 23

[0077] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface of the mainpole opposite to the perpendicular magnetic recording medium to define atrack width, that is, a pole tip, and in the main pole, part or all of aflux enhanced part in which the area of the cross section in parallelwith the air bearing surface is decreased as it approaches the airbearing surface and a position of the flux enhanced part closest to theair bearing surface, that is, a flux enhanced end are arranged on theleading side rather than a vertical plane in parallel with the crosstrack direction including the edge on the trailing side on the airbearing surface of the pole tip.

Embodiment 24

[0078] An invention described in this embodiment is a magnetic disk unitwherein in the perpendicular recording head according to embodiment 23,part or all of the flux enhanced part or the flux enhanced end of themain pole is arranged on the leading side rather than a vertical planeincluding the edge on the leading side of the air bearing surface of thepole tip.

Embodiment 25

[0079] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface of the mainpole opposite to the perpendicular magnetic recording medium to define atrack width, that is, a pole tip, and in the pole tip, part or all ofthe front surface on the trailing side of the pole tip in the airbearing height direction viewed from the air bearing surface of the poletip intersecting an air bearing surface is arranged on the leading siderather than a vertical plane in parallel with the cross track directionincluding the edge on the trailing side on the air bearing surface ofthe pole tip.

Embodiment 26

[0080] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface of the mainpole opposite to the perpendicular magnetic recording medium to define atrack width, that is, a pole tip, and in the pole tip, part or all ofthe side surface intersecting the cross track direction is arranged onthe center side of the pole tip rather than a vertical planeperpendicular to the cross track direction including the edge of thecross track direction of the edge on the trailing side of the airbearing surface of the pole tip.

Embodiment 27

[0081] An invention described in this embodiment is a magnetic disk unitincluding a magnetic head slider equipped with a thin film magnetic headhaving a single-pole type perpendicular recording head and a read headwith a reading element; a perpendicular magnetic recording medium havinga soft magnetic underlayer; and a spindle motor for rotating theperpendicular magnetic recording medium in a fixed direction; and a readchannel IC circuit for processing magnetic information inputted andoutputted through the recording head or the read head, wherein theperpendicular recording head has a main pole and an auxiliary pole, themain pole has a portion exposed to an air bearing surface of the mainpole opposite to the perpendicular magnetic recording medium to define atrack width, that is, a pole tip, and in the pole tip, part or all of aflux enhanced part in which the area of the cross section in parallelwith the air bearing surface is decreased as it approaches the airbearing surface and a position of the flux enhanced part closest to theair bearing surface are arranged on the leading side rather than avertical plane in parallel with the cross track direction including theedge on the trailing side of the air bearing surface of the pole tip.

Embodiment 28

[0082] An invention described in this embodiment is a magnetic disk unitwherein in the main pole of the perpendicular recording head accordingto embodiment 27, wherein part or all of the flux enhanced part or theflux enhanced end is arranged on the leading side rather than a verticalplane in parallel with the cross track direction including the edge onthe leading side of the air bearing surface of the pole tip.

[0083] The magnetic disk units of embodiments 19 to 28 are structured torealize recording by a magnetic field profile whose gradient is steepand enhance a liner density in the disk rotating direction and a trackdensity in the disk radius direction, thereby realizing a high arealrecording density.

Embodiment 29

[0084] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with amagnetic head slider, including the steps of:

[0085] forming a resist pattern on a non-organic layer;

[0086] forming a magnetic layer as a main pole on the inorganicinsulating layer formed with the resist pattern;

[0087] removing the resist pattern;

[0088] flattening the top of the magnetic layer and the top of theinorganic insulating layer with the resist pattern removed;

[0089] forming a resist pattern; and

[0090] sequentially forming a magnetic layer as the pole tip on theinorganic insulating layer and the magnetic layer formed with the resistpattern.

Embodiment 30

[0091] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with thesame, the production method according to embodiment 29, including thesteps of:

[0092] forming a resist pattern on a magnetic layer as the pole tip; and

[0093] forming a slope on the pole tip with the resist pattern as amask.

Embodiment 31

[0094] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with thesame, including the steps of:

[0095] forming a resist pattern on a non-organic layer;

[0096] forming a magnetic layer as a main pole on the inorganicinsulating layer formed with the resist pattern;

[0097] removing the resist pattern;

[0098] flattening the top of the magnetic layer and the top of theinorganic insulating layer with the resist pattern removed to form aresist pattern; and

[0099] repeating twice or more a step of sequentially forming a magneticlayer on the magnetic layer formed with the resist pattern.

Embodiment 32

[0100] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with thesame, including the steps of:

[0101] forming a resist pattern on a inorganic insulating layer;

[0102] forming a magnetic layer as a main pole on the inorganicinsulating layer formed with the resist pattern;

[0103] removing the resist pattern;

[0104] flattening the top of the magnetic layer and the top of theinorganic insulating layer with the resist pattern removed to form aresist pattern on the magnetic layer or the magnetic layer and thenon-organic layer;

[0105] sputtering the inorganic insulating layer and removing the resistpattern and the inorganic insulating layer attached thereto to form aslope;

[0106] forming a resist pattern; and

[0107] forming a magnetic layer as the pole tip on the inorganicinsulating layer and the magnetic layer formed with the resist pattern.

Embodiment 33

[0108] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with thesame, which sequentially perform the steps of:

[0109] forming a resist pattern on a inorganic insulating layer,sputtering the inorganic insulating layer, and removing the resistpattern and the non-organic layer attached thereto to from a slope;

[0110] forming a resist pattern; and

[0111] forming a inorganic insulating layer formed with the resistpattern and a magnetic layer as the main pole.

Embodiment 34

[0112] An invention described in this embodiment is the magnetic headfor perpendicular magnetic recording according to embodiments 1 to 6, afabrication method thereof, and a magnetic disk unit equipped with thesame, which sequentially perform the steps of:

[0113] forming a resist pattern on a inorganic insulating layer;

[0114] forming a slope on the inorganic insulating layer with the resistpattern as a mask; and

[0115] forming a resist pattern on the inorganic insulating layer toform a magnetic layer on the inorganic insulating layer formed with theresist pattern.

[0116] The magnetic disk units of embodiments 29 to 34 are structured torealize recording by a magnetic field profile whose gradient is steepand enhance a liner density in the disk rotating direction and a trackdensity in the disk radius direction, thereby realizing a high surfacerecording density.

[0117] The present invention can reduce the influence of the leakagemagnetic flux from the flux enhanced part and the flux enhanced end of amain pole and the front or side surface of the main pole, and cansteepen the field gradient of a perpendicular magnetic field on thetrailing side of the main pole and both edge sides of a track, so that ahigher areal recording density can be realized.

What is claimed is:
 1. A magnetic head for perpendicular recordinghaving a main pole and an auxiliary pole, comprising: in said main pole,part or all of a flux enhanced part in which the area of the crosssection in parallel with an air bearing surface is decreased as itapproaches the air bearing surface and a position of the flux enhancedpart closest to the air bearing surface, that is, a flux enhanced endbeing arranged on the leading side of said main pole rather than avertical plane in parallel with the cross track direction including theedge on the trailing side of said air bearing surface.
 2. A magnetichead for perpendicular recording according to claim 1, wherein in themain pole, part or all of said flux enhanced part or said flux enhancedend is arranged on the leading side rather than a vertical plane inparallel with the cross track direction including the edge on theleading side of said air bearing surface.
 3. A magnetic head forperpendicular recording having a main pole and an auxiliary pole,comprising: in said main pole, part or all of the front surface on thetrailing side of the main pole in the air bearing height directionviewed from the air bearing surface intersecting the air bearing surfacebeing arranged on the leading side rather than a vertical plane inparallel with the cross track direction including the edge on thetrailing side of the air bearing surface of the main pole.
 4. A magnetichead for perpendicular recording having a main pole and an auxiliarypole, comprising: in said main pole, part or all of the side surfaceintersecting the cross track direction of said main pole being arrangedon the center side of the main pole rather than a vertical planeperpendicular to the cross track direction including the edge of thecross track direction of an air bearing surface.
 5. A magnetic head forperpendicular recording having a main pole and an auxiliary pole,comprising: said main pole having a portion exposed to an air bearingsurface to define a track width, that is, a pole tip; and in said mainpole, part or all of a flux enhanced part in which the area of the crosssection in parallel with an air bearing surface is decreased as itapproaches the air bearing surface and a position of the flux enhancedpart closest to the air bearing surface, that is, a flux enhanced endbeing arranged on the leading side of said pole tip rather than avertical plane in parallel with the cross track direction including theedge on the trailing side of the air bearing surface of the pole tip. 6.The magnetic head for perpendicular recording according to claim 5,wherein in said main pole, part or all of the flux enhanced part or theflux enhanced end is arranged on the leading side rather than a verticalplane including the edge on the leading side of the air bearing surfaceof said pole tip.
 7. A magnetic head for perpendicular recording, in athin film magnetic head having a single-pole type perpendicularrecording head for recording, comprising: the perpendicular recordinghead having a main pole and an auxiliary pole; said main pole having aportion exposed to an air bearing surface to define a track width, thatis, a pole tip; and in said pole tip, part or all of the front surfaceon the trailing side of the pole tip in the air bearing height directionviewed from the air bearing surface of said pole tip intersecting theair bearing surface being arranged on the leading side rather than avertical plane in parallel with the cross track direction including theedge on the trailing side of the air bearing surface of the pole tip. 8.A magnetic head for perpendicular recording, in a thin film magnetichead having a single-pole type perpendicular recording head forrecording, comprising: the perpendicular recording head having a mainpole and an auxiliary pole; said main pole has a portion exposed to anair bearing surface to define a track width, that is, a pole tip; and insaid pole tip, part or all of the side surface intersecting the crosstrack direction being arranged on the center side of the pole tip ratherthan a vertical plane perpendicular to the cross track directionincluding the edge in the cross track direction of the air bearingsurface of the pole tip.
 9. A magnetic head for perpendicular recording,in a thin film magnetic head having a single-pole type perpendicularrecording head for recording, comprising: the perpendicular recordinghead having a main pole and an auxiliary pole; the main pole having aportion exposed to an air bearing surface to define a track width, thatis, a pole tip; and in said pole tip, part or all of a flux enhancedpart in which the area of the cross section in parallel with the airbearing surface is decreased as it approaches the air bearing surfaceand a position of the flux enhanced part closest to the air bearingsurface, that is, a flux enhanced end being arranged on the leading siderather than a vertical plane in parallel with the cross track directionincluding the edge on the trailing side of the air bearing surface ofthe pole tip.
 10. The magnetic head for perpendicular recordingaccording to claim 9, wherein in the main pole, part or all of said fluxenhanced part or the flux enhanced end is arranged on the leading siderather than a vertical plane in parallel with the cross track directionincluding the edge on the leading side of said air bearing surface.